Cementing tool



J. C. HOLDEN CEMENTING TOOL Sept. 15, 1964 2 Sheets-Sheet 1 Filed Aug. 2, 1961 WNVENTOR mam n John 6, Holden ATTORNEYS Sept. 15, 1964 J. c. HOLDEN 3,143,731

CEMENTING TOOL Filed Aug. 2, 1961 2 Sheets-Sheet 2 ENTQ John 0. Home United States Patent 3,148,731 CEMENTING T001.

John C. Holden, Duncan, Okla, assignor to Hallihurton Company, Duncan, (91th., a corporation of Delaware Filed Aug. 2, 1961, Ser. No. 128,860 11 Claims. (Cl. 166-184) This invention relates to cementing apparatus and, more particularly, to a formation packer shoe with an automatic fill-up unit.

One method of cementing well casings is to run a packer type cementing shoe on the end of a casing string. The packer is expanded at the desired depth to segregate a lower hole portion from the hydrostatic pressure of the cement column and to form a foundation for the wet cement. Ports are usually provided in the cementing shoe above a packer and cement is pumped down the casing and out through the ports. A flapper valve or check valve must be incorporated in the cementing shoe assembly to prevent the cement from flowing back into the casing after placement in the annulus between the casing and the well bore wall.

In cementing shoes having conventional flapper or check Valves there is no communication between the well bore and the interior of the casing since the valve is closed while the casing is being run in the hole. Therefore, as the cementing string is lowered, it tends to float on the mud and cause formation damaging pressure surges farther down the hole. To overcome this time consuming floating effect, it heretofore has been a usual practice to load strings with fluid. This technique, however, introduces problems of loading fluid disposal and does not alleviate the surges imposed by the closed string.

In cementing operations where packers have been included in cementing strings, it has normally been necessary to provide complex packer setting structures which have further complicated and delayed the cementing steps.

In recognition of the need for an improved cementing apparatus, it is an object of this invention to provide an improved packer type cementing shoe by means of which flotation problems are minimized.

It is a further object of this invention to provide a cementing shoe which contains a normally open fill-up valve which permits mud to enter the casing during running in of the casing string, but which may be selectively closed prior to a cementing step.

It is a particular object of this invention to provide a packer type cementing shoe with an automatic fill-up valve as described.

A final object of the invention is to provide a packer type cementing shoe in which an automatic fill-up valve is incorporated in a packer setting structure so as to especially facilitate cementing operations.

According to a preferred embodiment of the invention, a valved, packer-type setting tool is secured to the end of a cementing string. In the tool, a spring loaded float valve is mounted within a hollow mandrel adjacent the end of the string. The mandrel extends downward past the float valve and at its upper end is provided with longitudinally elongated slots or ports. A guide shoe and a mandrel encircling, radially expandable packer are secured to the lower end of the mandrel. The packer is expanded by a top packer shoe which encircles and slides longitudinally on the mandrel. Shear screws which extend from the top packer shoe into the mandrel, temporarily prevent relative movement between the shoe and mandrel.

A sleeve, provided with radial ports, is mounted within the mandrel below the float valve. The sleeve is interconnected with the top packer shoe by connecting pins which pass through the longitudinal slots in the mandrel. A tube is secured by shear pins to the lower end of the sleeve and extends upward into the valve body to obstruct the spring induced closing of the float valve. In the upper end of the tube there is provided an annular valve seat. A setting ring is mounted in the top of the float valve body and is provided with a valve seat forming an orifice which is positioned over the end of the tube. The orifice is slightly larger in diameter than the valve seat in the upper end of the tube. A third valve seat is formed on the interior of the sleeve adjacent its lower end.

The packer is set by first dropping a small ball down the string. It lodges in the annular valve seat formed in the tube. Pressure is then applied to the fluid in the pipe and at a certain pressure the shear pins on the bottom of the tube are sheared 0E and the tube is then pumped out through the guide shoe. With the tube thus removed, the spring operated float valve closes to prevent fluid flow upward through the string. The packer shoe can then be floated into place. When the packer setting depth is reached, a large ball is dropped down the pipe which lodges on the setting ring seat above the float valve. Pressure is then applied to the fluid in the pipe and at a certain pressure the shear screws between the top packer shoe and mandrel are sheared so that the top packer shoe and the interconnected sleeve move downward on the mandrel to longitudinally compress and thus radially expand the packer against the wall of the hole. Lock rings on the packer shoe engage circumferential grooves on the outer mandrel surface to maintain the packer in its expanded position. When the packer is expanded, the slots in the upper end of the mandrel are aligned with the ports in the sleeve to form passageways for cement to flow out of the casing and into the well bore annulus above the packer.

As the pressure builds up higher, the large ball deforms the opening in the setting ring and drops down to the seat in the bottom of the sleeve. This blocks the flow of cement out through the bottom of the tool. Cement may then be flowed down through the float valve and outward through the aligned sleeve ports and mandrel slots to the exterior of the casing above the packer. The float valve prevents reverse flow of the cementing fluid to the interior of the casing after the pumping is stopped. All of the internal parts of the cementing shoe are drillable so that they may be removed after the cement has set.

This preferred embodiment of the invention is illustrated in the accompanying drawings, in which:

FIGURE 1 is a cross sectional view of a well bore in which the packer type cementing shoe of this invention is suspended;

FIGURE 2 is a cross sectional view of the cementing shoe before expansion of the packer, along the line 22 in FIGURE 1;

FIGURE 3 is a cross sectional view of the cementing shoe after the packer has been expanded and the tube has been removed;

FIGURE 4 is a cross sectional view of the cementing shoe along the line 4-4 in FIGURE 2;

FIGURE 5 is a cross sectional view of the cementing shoe along the line 55 in FIGURE 3.

Referring to FIGURES 1 and 2, the packer assembly is secured to the end of a casing string 1. A casing section 2 is secured to the string 1 by an internally threaded ring 3 which engages threads on the casing 1. The collar 3 is secured to the casing section 2 by a weld or other suitable means. A casing or mandrel 4 is telescoped within and welded to the casing section 2 while a guide shoe 5 is secured to the lower end of the mandrel 4. Also mounted on the mandrel 4 is a top packer shoe 6 which abuts against a shoulder 7 on the lower end of the casing section 2. The top packer shoe 6 is secured against movement relative to the mandrel 4 by means of screws 8 which extend through the packer shoe and through the mandrel.

While the number of screws is optional, as shown in FIG- URE 4, there may be three screws 8 spaced around the circumference of the mandrel 4. A plurality of lock rings 9 are mounted within recesses in the internal circumference of the packer shoe 6. Below the lock rings 9, a series of circumferential grooves 10 on the mandrel 4 are adapted to be engaged by the lock rings 9. An expandable packer 11 is mounted on the mandrel 4 so that one end abuts a shoulder on the guide shoe 5 and the opposite end abuts a shoulder on the top packer shoe 6. Downward movement of the top packer shoe 6 compresses the packer 11 and causes it to bulge radially outward against the wall of the hole.

A drillable valve body 12 is slidably mounted at the top of the mandrel 4 and a pair of 0rings 13 form a seal between the valve body and the mandrel. The valve body 12 is provided with a central port 14. At the top of the valve body 12, the port 14 is expanded to form a flange in which a setting ring 15 is mounted. The setting ring 15 is secured in the port 14 by pins 15a which extend through the setting ring 15 and into the valve body 12. The setting ring 15 is provided with a seat defining orifice 16 for the passage of fluid. Orifice 16 is somewhat larger than the opening in the upper end of tube 21. Directly below the valve body 12 and defining a continuation thereof, a hollow sleeve 17 is slidably mounted within the mandrel 4. As illustrated, sleeve 17 defines a hollow chamber beneath port 14 in valve body means 12 and 17. Sleeve 17 is preferably of drillable plastic. O-rings 18 on the exterior of the sleeve maintain a fluid seal between the mandrel and the sleeve. The lower end of the sleeve 17 is provided with an internal valve seat 19 having a bore 20 passing through the bottom of the sleeve. A tube 21, also of drillable plastic or aluminum, has a tube retainer collar 22 threaded on one end. This collar is detachably mounted in the lower portion of the bore 20 so that the tube 21 extends upward through the sleeve. Rods 23, preferably of plastic material, extend through the sleeve 17 and into the retainer collar 22 to secure the collar 22 and the tube 21 within the bore 20.

The tube 21 extends upwardly through the sleeve 17 and into the port 14. The internal diameter of the top portion of the tube is somewhat larger than that of the lower portion of the tube so that a valve seat 24 is formed at the junction of these two portions. A flapper valve 25 is hingedly mounted on the valve body 12 below the port 14. A spring 26 on the hinge of the valve 25 urges the valve closed. A valve seat 27 adjacent the bore 14 is engaged by the valve 25 when it closes to prevent fluid from flowing upward through the casing section 2 and string 1. The tube 21, however, when extended into the port 14, blocks the closing of the flapper valve 25 and maintains it in the open position.

A plurality of longitudinally elongated ports 28 are provided around the circumference of the sleeve 17. One of the ports 28 is enlarged to accommodate the flapper valve 25 in its open position, as shown in FIG. 2. Elongated slots or ports 29 are also provided in the mandrel 4. Connecting pins 30 are mounted in holes in the top packer shoe 6 and the sleeve 17 and extend through the slots 29 in the mandrel, as shown in FIGURES 2 and 4. The connecting pins 30 are secured in place by stakes 31 which extend through the wall of the packer shoe 6 and into the connecting pins 30. While the number of pins, ports, and slots may be varied, three each are contemplated in the preferred structure.

The ports 28 in the sleeve 17 and the slots 29 in the mandrel 4 are in radial alignment, but displaced longitudinally when the packer is in its retracted position, as shown in FIGURE 2. The slots 29 in the mandrel 4 form guides for the connecting pins 30. When the sleeve 17 and valve body 12 move downward, the motion is transmitted by the pins 30 to the top packer shoe 6. In the lowermost position of the top packer shoe 6, as shown in FIGURES 3 and 5, the ports 28 in the sleeve 17 are in alignment with the slots 29 in the mandrel 4 to form passageways between the interior of the sleeve and the outside of the mandrel opening above the packer 11.

The operation of the tool will now be described with reference to an exemplary embodiment of the tool in which the seat at orifice 16 and the seat 19 are dimensioned to retain a 1% inch diameter ball while seat 24 is dimensioned to retain a 1% inch diameter ball. The small, 1% inch ball 32 is dropped first into the string 1. The ball 32 passes through the orifice 16 and lodges in the valve seat 24 in the tube 21. Pressure is then applied to the fluid in the string 1 until, at about 200 p.s.i., for example, the pressure on the ball 32 is suflicient to shear the rods 23 and pump the tube 21 out through the bottom of the shoe. Since the tube 21 no longer blocks the flapper valve 25, it is closed by its spring 26 when the fluid pressure in the pipe 1 is reduced.

The packer 11 is set at the desired depth by dropping the larger, 1% inch ball 33 down the string 1. The ball 33 becomes lodged in the orifice 16 of the shear ring 15, thus blocking the flow of fluid downward through the port 14. Pressure is then applied to the fluid in the string 1 until, at about 400 p.s.i., for example, the screws 8 are sheared to permit the valve body 12, the connected sleeve 17, and packer shoe 6 to move downward to expand the packer 11. In the extended position, as shown in FIGURES 3 and 5, the slots 29 in the mandrel 4 are partially uncovered and aligned with the ports 28 in the sleeve 17 to form passageways through the tool wall above the packer 11. The lock rings 2 on the top packer shoe 6 engage the grooves 10 in the mandrel to maintain the shoe 6 in its expanded position.

Before cementing can begin, the bore 20 in the bottom of the sleeve 17 must be closed. This is accomplished by increasing the pressure in the string 1 until, at about 1200 p.s.i., for example, the ball 33 deforms or ruptures the setting ring 15, drops through the port 14 and lodges in the valve seat 19, as shown in phantom line in FIG. 3. In this position, the ball 33 prevents cementing fluid from being pumped out through the bottom of the sleeve, causing it to flow outward through the aligned openings 28 and 29. Cement may then be pumped through the flapper valve, out through the aligned openings 28 and 29, and upward around the casing above the packer 11. When the pumping is stopped, the flapper valve 25 closes to prevent the cement in the well from being pumped back into the pipe by its own hydrostatic pressure.

In operation, as the packer type cementing shoe is lowered into the hole on the bottom of the casing string 1, fluid in the hole enters the casing through the guide shoe 5 and through the tube 21. Circulation may be established at any time during running of the pipe, since there are no obstructions between the interior of the string and the well hole. When fill-up is to be stopped, the small ball is dropped down the string 1 and the casing fluid pressure raised to dislodge the tube 21 and thus allow check valve 25 to close. The cementing shoe can then be floated into place for the terminal portion of string placement.

The principal advantages of the combined packer and automatic fill-up float valve are that circulation can be established through the fill-up unit without tripping the valve and that the self fill-up unit can be tripped at any time. Also, the unit operates eificiently in mud containing a high percentage of lost circulation materials. Of particular advantage is the ease with which the fill-up may be terminated and the packer set to commence cementing operations.

In addition to the foregoing beneficial structural characteristic of the tool, a further advantage results from the tube type of check valve retainer. The tube defines a passage through the hollow interior of the sleeve tending to shield the sleeve openings and valve parts from debris accumulation.

While the invention has been illustrated and described in one embodiment, it is recognized that variations and changes may be made therein without departing from the invention as set forth in the claims.

I claim:

1. A cementing tool comprising: a mandrel having radial ports, means for attaching the mandrel to a casing string, a valve body mounted within the mandrel, said valve body having a chamber formed in the lower portion thereof and a deformable orifice thereabove, said valve body further having radial ports communicating with said chamber, said mandrel ports being in the same radial plane as the chamber ports but spaced axially therefrom, a valve seat in the chamber, frangible holding means for preventing relative movement between the valve body and mandrel until a first predetermined fluid pressure is applied to the valve body, and a plug for closing the orifice in said valve body for applying fluid pressure to the valve body, thereby moving said chamber and mandrel ports into alignment, said orifice being deformed at a second predetermined fluid pressure to pass the plug therethrough whereby the plug lodges in said valve seat to close the lower end of said chamber, said first pressure being lower than said second pressure.

2. A formation packer shoe comprising: a mandrel, means for attaching the mandrel to a casing string, a valve body mounted vwthin the mandrel having a port and an orifice thereabove, valve means in the valve body adjacent the port, means biasing the valve means into closing position across the port, obstruction means in the port having a conduit therethrough and preventing closure of the valve means, an expandable packer mounted on the mandrel, means on the mandrel for expanding the packer, means connecting the valve body and expanding means for axial movement thereby, frangible means for securing the obstruction means in the port until a first predetermined pressure is applied to the obstruction means, shoulder means in the conduit for cooperation with a plug for applying the first predetermined pressure to the obstruction means to remove the obstruction means thereby permitting the valve means to close, and frangible holding means for preventing relative movement between the valve body and the mandrel until a second predetermined pressure is applied to the valve body, whereby when a second plug is inserted in the mandrel to lodge in the orifice and a second predetermined pressure is thereby imposed on the valve body to break the holding means, the expanding means is moved to expand the packer.

3. A cementing tool comprising: a mandrel having radial ports, means for attaching the mandrel to a casing string, a valve body mounted within the mandrel, said valve body having a chamber formed in the lower portion thereof and an orifice thereabove, said valve body further having radial ports communicating with said chamber, said mandrel ports being in the same radial plane as the chamber ports but spaced axially therefrom, a valve seat in the chamber, frangible holding means for preventing relative movement between the valve body and mandrel until a predetermined pressure is applied to the valve body, and means for closing the orifice in said valve body whereby fluid pressure may be applied to the valve body to overcome the holding means to move the valve body ports into alignment with the casing ports, one of said closing means and said orifice being deformable whereby said closing means is displaced from said orifice to said valve seat in the chamber in response to a pressure higher than said predetermined pressure.

4. A fill-up tool comprising: a hollow cylinder, a first wall, a second wall, said walls extending across the cylinder and being spaced apart in said cylinder and forming a chamber therebetween, said first wall having a port therein, a valve pivotally mounted in the chamber and movable to close the port, means biasing the valve to a closed position, said second wall having an opening therein, a tube extending from the opening to the port through the chamber for blocking the valve open, frangible means mounting the tube in the opening, and means for removing the tube from the chamber in response to fluid pressure.

5. A formation packer shoe comprising: a mandrel having radial ports, means for attaching the mandrel to a casing string, an expandable packer mounted on the mandrel, a packer shoe on the mandrel, a valve body mounted within the mandrel, said valve body having a chamber in the lower portion thereof and an orifice thereabove, said valve body further having radial ports communicating with said chamber, said mandrel ports being in the same radial plane as the valve body ports but spaced axially therefrom, means for connecting together the packer shoe and the valve body, frangible holding means for preventing relative movement between the valve body and the mandrel until a predetermined pressure is applied to the valve body, said valve body having a valve seat in the chamber below said body ports, and means for closing the valve body orifice whereby fluid pressure may be applied to the valve body to overcome the holding means to axially move said valve body and packer shoe such that the body ports are moved into alignment with the mandrel ports and the" packer is expanded, one of said orifice and said closing means being deformable whereby said closing means is displaced from said orifice to the valve seat in response to a pressure higher than said predetermined pressure.

6. A formation packer shoe comprising: a mandrel having radial ports, means for attaching the mandrel to a casing string, an expandable packer mounted on the mandrel, a packer shoe on the mandrel, a valve body mounted within the mandrel, said valve body having a chamber in the lower portion thereof and an orifice thereabove, said valve body further having radial ports communicating with said chamber, said mandrel ports being in the same radial plane as the valve body ports but spaced axially therefrom, means for connecting together the packer shoe and the valve body, frangible holding means for preventing relative movement between the valve body and the mandrel until a predetermined pressure is applied to the valve body, said valve body having a valve seat in the chamber below said body ports and having an axial port between said body ports and said orifice, valve means in the valve body adjacent said axial port, means biasing the valve means into closing position across the port for preventing upward flow of fluid from the chamber through the orifice, and means for closing the valve body orifice whereby fluid pressure may be applied to the valve body to break the holding means to axially move said valve body and packer shoe such that the body ports are moved into alignment with the mandrel ports and the packer is expanded, one of said orifices and said closing means being deformable whereby said closing means is displaced from said orifice to the valve seat in response to a pressure higher than said predetermined pressure.

7. A formation packer shoe comprising a mandrel, means for attaching the mandrel to a casing string, a valve body having upper and lower ends mounted within the mandrel, said valve body having a deformable orifice in said upper end, a valve seat in the lower end, and a chamber between the orifice and the valve seat, said valve body having an axial port between the orifice and the chamber, valve means in the valve body adjacent the port, spring means biasing the valve means into closing position across the port, an expandable packer mounted on the mandrel, a packer shoe on the mandrel adjacent the packer, frangible means for preventing relative movement between the valve body and the mandrel until a predetermined pressure is applied to the valve body, said mandrel having radial ports, said valve body having openings communicating with the chamber and being in the same radial plane as the mandrel ports, but spaced axially thereabove, means for securing together the valve body and the packer shoe for axial movement relative to the mandrel, a tube extending through the chamber and into the valve body port in position to prevent closing of the valve means, said tube having a smaller internal diameter than that of the orifice and having a shoulder therein, and frangible supporting means for securing the tube in the port, whereby when a small ball is lodged in the tube and a pressure less than said predetermined pressure is applied to the valve body the tube is displaced out of the chamber, and when a large ball is lodged in the orifice and said predetermined pressure is applied to the valve body the packer is expanded, and when a pressure higher than said predetermined pressure is applied, the orifice is deformed and the large ball is displaced to the valve seat.

8. A formation packer shoe comprising: a mandrel having radial ports, means for attaching the mandrel to a casing string, an expandable packer mounted on the mandrel, a packer shoe on the mandrel, a valve body mounted within the mandrel, said valve body having a chamber in the lower portion thereof and an orifice thereabove, said valve body further having radial ports communicating with said chamber, said mandrel ports being in the same radial plane as the valve body ports but spaced axially therefrom, a pin extending through one of said mandrel ports and being secured at opposite ends to said packer shoe and said valve body, frangible holding means for preventing relative movement between the the valve body and the mandrel until a predetermined pressure is applied to the valve body, said valve body having a valve seat in the chamber below said body ports, said valve body having an axial port between said radial ports and said orifice, valve means in the valve body adjacent the port, means biasing the valve means into closing position across the port for preventing upward flow of fluid from the chamber through the orifice, and means for closing the valve body orifice whereby fluid pressure may be applied to the valve body to overcome the holding means to axially move said valve body and packer shoe such that the body ports are moved into alignment with the mandrel ports and the packer is expanded, one of said orifice and said closing means being deformable whereby said closing means is displaced from said orifice to the valve seat in response to a pressure higher than said predetermined pressure.

9. A formation packer shoe comprising: a mandrel, means for attaching the mandrel to a casing string, a valve body mounted within the mandrel having a port therein, a plate having an orifice therein in axial alignment with the port, frangible means mounting the plate in the valve body between the port and said attaching means, valve means in the valve body adjacent the port, means biasing the valve means into closing position across the port, an expandable packer mounted on the mandrel, means on the mandrel for expanding the packer, means connecting the valve body and expanding means for axial movement thereby, said valve body having an axial bore therein below said valve means, a tube extending between said bore and said port for blocking said vaive in open posi tion, frangible means for securing the tube in the bore until a first predetermined pressure is applied to the bstruction means, said tube having a shoulder therein for cooperation with a plug for applying said first pressure to the tube to remove the tube, thereby permitting the valve means to close, and frangible holding means for preventing relative movement between the valve body and the mandrel until a second predetermined pressure is applied to the valve body, whereby when a second plug is inserted in the mandrel to lodge in the orifice and a second predetermined pressure is thereby imposed on the valve body to break the holding means, the expanding means is moved to expand the packer.

10, A formation packer shoe comprising: a mandrel, means for attaching the mandrel to a casing string, a valve body mounted within the mandrel having a port therein, a plate having an orifice therein in axial alignment with the port, frangible means mounting the plate in the valve body between the port and said attaching means, valve means in the valve body adjacent the port, means biasing the valve means into closing position across the port, an expandable packer mounted on the mandrel, means on the mandrel for expanding the packer, means connecting the valve body and expanding means for axial movement thereby, said valve body having an axial bore therein below said valve means, a tube extending between said bore and said port for blocking said valve in open position, frangible means for securing the tube in the bore until a first predetermined pressure is applied to the obstruction means, said tube having a tube therein for cooperation with a plug for applying said first pressure to the tube to remove the tube thereby permitting the valve means to close, and frangible holding means for preventing relative movement between the valve body and the mandrel until a second predetermined pressure is applied to the valve body, whereby when a second plug is inserted in the mandrel to lodge in the orifice and a second predetermined pressure is thereby imposed on the valve body to break the holding means, the expanding means is moved to expand the packer.

11. A fill-up tool comprising: a hollow cylinder, means for attaching the cylinder to a casing string, a first wall, a second wall, said walls extending across the cylinder and being spaced apart in said cylinder and forming a chamber therebetween, said first wall having a port therein, a valve pivotally mounted in the chamber and movable to close the port, means biasing the valve to a closed position, said second wall having an opening therein, a tube extending from the opening to the port through the chamber for blocking the valve open, frangible means mounting the tube in the opening, said tube having a shoulder integral therewith for receiving a plug, whereby the tube is displaced out of the chamber when a plug is lodged on the shoulder and a predetermined pressure is applied, thereby permitting the valve to close the port.

References Cited in the file of this patent UNITED STATES PATENTS 2,488,819 Larltin Nov. 22, 1949 2,638,988 Williams May 19, 1953 2,762,440 Reed Sept. 11, 1956 2,768,695 Althouse Oct. 30, 1956 2,872,983 Renouf Feb. 10, 1959 2,925,865 Oliver Feb. 23, 1960 3,011,559 Muse Dec. 5, 1-961 

2. A FORMATION PACKER SHOE COMPRISING: A MANDREL, MEANS FOR ATTACHING THE MANDREL TO A CASING STRING, A VALVE BODY MOUNTED WITHIN THE MANDREL HAVING A PORT AND AN ORIFICE THEREABOVE, VALVE MEANS IN THE VALVE BODY ADJACENT THE PORT, MEANS BIASING THE VALVE MEANS INTO CLOSING POSITION ACROSS THE PORT, OBSTRUCTION MEANS IN THE PORT HAVING A CONDUIT THERETHROUGH AND PREVENTING CLOSURE OF THE VALVE MEANS, AN EXPANDABLE PACKER MOUNTED ON THE MANDREL, MEANS ON THE MANDREL FOR EXPANDING THE PACKER, MEANS CONNECTING THE VALVE BODY AND EXPANDING MEANS FOR AXIAL MOVEMENT THEREBY, FRANGIBLE MEANS FOR SECURING THE OBSTRUCTION MEANS IN THE PORT UNTIL A FIRST PREDETERMINED PRESSURE IS APPLIED TO THE OBSTRUCTION MEANS, SHOULDER MEANS IN THE CONDUIT FOR COOPERATION WITH A PLUG FOR APPLYING THE FIRST PREDETERMINED PRESSURE TO THE OBSTRUCTION MEANS TO REMOVE THE OBSTRUCTION MEANS THEREBY PERMITTING THE VALVE MEANS TO CLOSE, AND FRANGIBLE HOLDING MEANS FOR PREVENTING RELATIVE MOVEMENT BETWEEN THE VALVE BODY AND THE MANDREL UNTIL A SECOND PREDETERMINED PRESSURE IS APPLIED TO THE VALVE BODY, WHEREBY WHEN A SECOND PLUG IS INSERTED IN THE MANDREL TO LODGE IN THE ORIFICE AND A SECOND PREDETERMINED PRESSURE IS THEREBY IMPOSED ON THE VALVE BODY TO BREAK THE HOLDING MEANS, THE EXPANDING MEANS IS MOVED TO EXPAND THE PACKER. 